Design and Connections
Moving to the stand and it's plain to see, again, that this is designed to take the extra weight of a well built monitor. This is an optional extra and needs to be ordered separately from your panel order, so make sure you remember to buy one, unless of course you are wall mounting it. The stand is heavy and requires some construction when unpacked by adding two connection bars that screw to the stand and then into the back of the panel. This requires that you have to lay the panel down flat and then insert the stand mounts. Once you have put them together the stand and screen look good with excellent stability when table mounted. It will take quite a bit of shaking or movement to get the screen to fall over and it is almost impossible to tip this screen over accidentally.
Moving to the rear of the Panel and we find the two items that scream 'professional monitor' more than anything else, and that’s the two hand grips at the top of the panel. Also here are standard mounting points for wall mounting the panel as well as the connections and power point. Again as we are talking about a professional product here the connections are placed in the best possible position for wall mounting and point downwards from the back of the panel. Another difference over the consumer models is the connection ports. Here you can customise just what connections you use by buying additional input boards which simply slide into the bottom of the panel chassis. Included as standard is just one HDMI input, so if you want to connect any more HDMI devices you can either buy an extra input board, or use an external video switcher. Indeed an external switcher, AV Receiver or video processor is likely to be a 'must have' companion with a screen such as the PF20. Other standard connections include single DVI-D slot, VGA slot, one set of BNC components and composite video inputs along with audio inputs. There is also a RS232C control port, a LAN connection and finally, on the back plate, is the power cable connection (which is locked) and two external speaker terminals.
Moving to the remote control and we have a rather odd looking unit provided with the PF20. Owners of Panasonic projectors will recognise the small design used here and as this is a monitor, not a full fledged TV, there is no need for channel numbers and so on. The supplied remote is small yet functional and to be honest the likely owners of this panel will have had it installed as part of a fully controlled custom installation; so will probably never use the supplied remote control.
Menus and set up
Opening up the main picture menu we have a few, now standard, picture settings. First of all we select the picture mode we want to use and these are Normal, Dynamic, Cinema and Monitor. The Dynamic mode on this panel is certainly not as bad a setting as you will find on the consumer models and is far more restrained in its picture brightness and colour errors. The Monitor mode is very similar to the Cinema setting but has a restricted contrast level that you can’t over ride. In the end we found that the Cinema mode offered the most accurate out of the box setting to our reference standards. Under the picture mode selection we then have the main front panel controls, Brightness, Contrast, Colour, Hue and Sharpness. Also included here is the white balance selection which, like every other Panasonic Plasma, is best set to the Warm preset. Finally we have a setting called colour management, which, in fact, is nothing of the kind. This setting is more of a colour boost option which you can switch on or off and we suggest you leave it off as it increases saturation errors in the image.
Next up is the selection of the advanced menu which includes full white balance controls for greyscale set up. Also here is a selection of fixed gamma options as well as black extension and input level to offer further image adjustment (but we found these of no real use for what we were trying to achieve with the PF20). Sadly there is no 3D Colour Management system for adjusting the Hue, saturation and brightness of the RGBCYM colour points within the colour gamut. I find this omission very strange for a professional monitor and, in today’s market, that means the PF20 has less control than the consumer models for 2010. It will be interesting to see how the gamut measures later in the review.
Moving to the set up menus and we are given some interesting options that are completely inappropriate to our use of the PF20. These allow the monitor to act as digital signage by changing from a landscape image to a vertical one. This would allow business customers to purchase three PF20s and line them up vertically to show one large digital sign or video image. This is totally useless for home cinema use, but an interesting side track anyway. Other options in these menus include power driving selections, screensavers, languages and so on. These are all set once and forget features. We also have options for over scan and pixel 1:1 mapping with further aspect ratio selections.
Flicker, image retention and black levelsBecause of the way plasma displays work they can cause a small number of people to see image flicker on screen. With the PF20 I couldn’t see any flicker caused by the TV in any of its set up options. However this doesn’t mean that flicker is not there for some users so if you can; demo this screen before purchase.
Another problem seen in varying degrees with plasma screens is image retention. This is not to be confused with image burn-in which is permanent damage by burning an image or logo on screen. Image retention is on every plasma TV but it normally disappears within anything from a couple of minutes to a few of hours of normal use. I used a news channel with their over the top screen logos for an hour at a time to check for image retention. I did this by using a full raster 100ire test pattern from our Sencore generator. Results here were very good with no obvious retention seen during normal playback of material and only slight traces of channel logos when using a test pattern after an hour’s use of a news channel. I would not consider the level of retention on the PF20 to be any kind of problem for watching normal content on a daily basis as it is not visible without the use of test patterns.
Finally an issue that is causing concern for many forum members is the fact that Panasonic 2009 consumer models have been affected by rising black levels. A recent Panasonic statement has suggested that the 2010 consumer models will have the same rises but at a much reduced level and over a longer period in time. We have no further information about this from Panasonic to go on, so need to raise this issue for information purposes until we have some solid information, and results for the 2010 range. As the PF20 is a professional unit and as it appears to use a G13 panel, we cannot give any information on whether there will be any noticeable black level rises over its lifetime. Plus as we only have this review sample for a short period of time our measurements in this area are inconclusive.
Out of the box measurementsAs always with our display reviews we want to see how well the TV manages to get towards the industry standards for TV and Blu-ray playback. We have high hopes that a professional plasma display will be pretty good out of the box, as after all, it will be used in professional applications. We found our best out of the box settings were Cinema mode, with the white balance selected as Warm and the brightness and contrast set to our viewing environment with test patterns. This is the same set up any normal user will carry out; so just how close can the PF20 get to the reference standards?
It's when we move to the colour gamut measurements that things become slightly disappointing. For a professional panel the over extended gamut here, with oversaturation of red and green, plus the secondary colours, really is a poor result in this day and age. We would expect that any panel that proclaims to be suitable for use in the professional world should at least hit the industry standards for content playback. It’s frustrating to see such a wide gamut still being used. Thankfully the overall errors for luminance mean that colours are not unnecessarily pushed in brightness that would likely compound the errors. However, the sad point here is that there is no 3D colour management system (CMS) that will help us to correct the RGBCYM colour points during a calibration. We are going to have to rely on the quality of the colour decoder and hue control to try and balance the errors out once the Greyscale is correct.
Calibration resultsSo we move to our calibration and thankfully Panasonic has given us some control over the Greyscale set up by supplying the gain and bias controls for red, green and blue in the advanced white balance menu. This means that we should be able to get the colour of grey almost perfect and give us a perfect backbone to the rest of the image.
Moving to the gamut and without any CMS system it was impossible to correct the green errors by bringing it back to where it should be. However using the excellent colour decoder (main colour control) and then knocking Hue down by 1 we were able to even out the errors and get more of the points correct, or, as near as correct as possible. Luminance, Hue and overall errors were now acceptable with only the saturation points showing any errors. This actually translated very well to onscreen images of normal material as the vast majority of the palette looked natural, especially skin tones. This was measured and also referenced against our reference display that is perfect to the standards. Let's just say that although on the CIE chart green looks to be some distance away, this is a saturation error mainly, and is balanced with the same type of errors with blue and cyan. However, we would have been more concerned about the likes of red (which you would notice far more) when it comes to errors and the actual end result on screen matches up very well next to a reference point; with very small visual errors. To put it another way, if I sat a forum member down to watch both, I doubt they would see the errors on the PF20 as any major fault, unless the material being shown included strong greens or blues, and even then, it wouldn’t be a deal breaker. But of course if this professional plasma had the right tools to begin with…
A final point here is that using a VideoEQ Pro or high quality scaler with CMS is going to allow the PF20 to be calibrated correctly to reference levels and for once that type of user is going to be the PF20’s main customer as opposed to the consumer range from Panasonic.
Video ProcessingWith the PF20 the vast majority of users are going to be feeding it signals from either a set top box with scaling built in, a high quality AVR with the same, or a high quality scaler. As such the only hard task the PF20 is going to have is handling a 1080i signal. If an external AVR or scaler is used then issues like cadence detection and scaling performance will be handled off board before the signal is sent to the panel. As such, the video processing in the PF20 is pretty much adequate and thankfully doesn’t do any behind the scenes tinkering with incoming signals.
Gaming Lag timeWhilst it's not a screen you would buy for gaming, I didn’t measure any lag time over 10ms with three runs of the measurement.
Power consumptionUsing our standard test of static full rasters at 0, 50 and 100ire the PF20 measured 132w, 243w and 339w respectively. During a 10 minute run of normal material, (as plasma is a self illuminating technology and power consumption varies depending on what scenes are on screen) the lowest reading was 67w and the highest 278w.
Where the PF20 does do things well is with presenting a very clean and sharp looking image (with 1:1 pixel mapping) that also has excellent colour gradation control. This is one area where the professional screen does shine and as such the sharpness of image and the shadow detailing make the picture a very compelling one to watch. Even with its slight errors in colour saturation the PF20 looked excellent once it was calibrated correctly with believable skin tones and an excellent overall colour palette performance. Put against our reference the lack of black level is noticeable but in all other areas it looks good. Plus there was a lack of phosphor trailing that can still be an issue with the consumer sets in the mid range. So while dented by some aspects, the PF20 can still be considered a very good quality screen that knocks the socks off the latest LCD and LED LCD sets for sheer image quality, even with only ‘good’ black levels.
Where the PF20 will really shine is in systems with external calibration control. Whilst these won’t bring back deeper black levels, the PF20 can offer reference levels of accuracy with a videoEQ Pro (and likely the same with a high quality scaler with the right controls). This is where the PF20 is designed to be used and in such systems it really is a great quality monitor. It could have been even better by adding an ambient light filter, full calibration control with an accurate preset and the deeper blacks of the recently reviewed VT20.
- Good quality design
- Excellent build quality
- Customisable input boards
- External control interfaces
- Reference level Greyscale results
- Lack of PWM noise and sharp image quality
- Good colour performance despite slight inaccuracies
- Will work well with an external scaler or videoEQ system with CMS
- Good, but not perfect black levels
- Black levels not as strong as the recent consumer range from Panasonic
- No 3D Colour Management System for RGBCYM adjustment
- No accurate preset for [tip=Rec709]Rec.709[/tip] playback
- Requires excellent quality off board devices to get the best out of the image quality
- Still questions on Panasonic plasma black level and voltage rise issues
Panasonic PF20 (TH-42PF20) Review
This screen will appeal to those who want to feed the PF20 with quality images from an external scaler or video system and its major calling will be the custom installation market. It is not a bad display by any stretch of the imagination and it can offer up stunning reference grade accuracy with the correct devices attached. But we also can’t help but think ‘what if’ when comparing it to the likes of the G20 and VT20 plasmas from the consumer range. If Panasonic was to take on some of the feedback here and add in the same excellent black levels and accuracy of the consumer 2010 models, they might just produce a 'must have' plasma monitor. Sadly on this occasion it’s a near miss in our opinion.
Contrast/Dynamic Range/Black Level
Ease Of Use
Value for Money
Our Review Ethos
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